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Top Forums Shell Programming and Scripting Grab exactly one byte from a FIFO, at random intervals Post 302747897 by Yoda on Sunday 23rd of December 2012 03:56:40 PM
Old 12-23-2012
I don't know what magic it is but I'm getting it right!!
Code:
y: print next byte
n: don't print next byte
q: quit
y
The input byte is:
48  H
y: print next byte
n: don't print next byte
q: quit
y
The input byte is:
65  e
y: print next byte
n: don't print next byte
q: quit
y
The input byte is:
6c  l
y: print next byte
n: don't print next byte
q: quit
y
The input byte is:
6c  l
y: print next byte
n: don't print next byte
q: quit
y
The input byte is:
6f  o
y: print next byte
n: don't print next byte
q: quit
q

I tested it on GNU/Linux and shell /bin/bash

I recommend you to run ps and verify if you have any previous instance of this script & tail command running because I see the listening section is not getting gracefully terminated after selecting option q and I see this is causing the behavior that you mentioned.
Code:
# ps
  PID TTY          TIME CMD
 4787 pts/0    00:00:00 tail
 4788 pts/0    00:00:00 tfifo.sh
26804 pts/0    00:00:00 ps
29197 pts/0    00:00:00 bash

This User Gave Thanks to Yoda For This Post:
 

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WC(1)								   User Commands							     WC(1)

NAME
wc - print newline, word, and byte counts for each file SYNOPSIS
wc [OPTION]... [FILE]... wc [OPTION]... --files0-from=F DESCRIPTION
Print newline, word, and byte counts for each FILE, and a total line if more than one FILE is specified. With no FILE, or when FILE is -, read standard input. A word is a non-zero-length sequence of characters delimited by white space. The options below may be used to select which counts are printed, always in the following order: newline, word, character, byte, maximum line length. -c, --bytes print the byte counts -m, --chars print the character counts -l, --lines print the newline counts --files0-from=F read input from the files specified by NUL-terminated names in file F; If F is - then read names from standard input -L, --max-line-length print the length of the longest line -w, --words print the word counts --help display this help and exit --version output version information and exit AUTHOR
Written by Paul Rubin and David MacKenzie. REPORTING BUGS
Report wc bugs to bug-coreutils@gnu.org GNU coreutils home page: <http://www.gnu.org/software/coreutils/> General help using GNU software: <http://www.gnu.org/gethelp/> Report wc translation bugs to <http://translationproject.org/team/> COPYRIGHT
Copyright (C) 2011 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. SEE ALSO
The full documentation for wc is maintained as a Texinfo manual. If the info and wc programs are properly installed at your site, the com- mand info coreutils 'wc invocation' should give you access to the complete manual. GNU coreutils 8.12.197-032bb September 2011 WC(1)
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